secure adj
1 immune, impregnable, in safe hands, out of harm's way, protected, safe, sheltered, shielded, unassailable, undamaged, unharmed
2 dependable, fast, fastened, firm, fixed, fortified, immovable, stable, steady, tight
3 assured, certain, confident, easy, reassured, sure
4 absolute, conclusive, definite, in the bag (informal) reliable, solid, steadfast, tried and true, well-founded vb
5 acquire, come by, gain, get, get hold of, land (informal) make sure of, obtain, pick up, procure, score (slang) win possession of
6 attach, batten down, bolt, chain, fasten, fix, lash, lock, lock up, make fast, moor, padlock, rivet, tie up
7 assure, ensure, guarantee, insure adj endangered, ill-at-ease, insecure, loose, not fastened, precarious, unassured, uncertain, uneasy, unfixed, unprotected, unsafe, unsound, unsure vb endanger, give up, imperil, leave unguaranteed, let (something) slip through (one's) fingers, loose, lose, unloose, untie